Piston water-meter



(Model.) 2 Sheets-Sheet I.

J. A. TILDEN.

PISTUN WATER METER.

No1 251,971.` Patented Jan. 3,1882.

N. Parras. mwumngmpher. wmmgmn. u. c

(Model.) I ZSheets-'Sheet 2. J. A. TILDEN.

BISTON WATER MBT-ER. No. 251,971. Patented Jan. 3,1882.

6W? WMV UNITED STATES 'PATENT OFFICE.

JAMES A. TILDEN, oE HYDE PARK, AsSrGNoH E oNEHAT-.E To FRANCIS o.

HEESEY, 0E SOUTH BosToN, MASSACHUSETTS.

SPECIFICATION forming part of Letters Patent No. 251,971,'dated January 3, 1882.

Application tiled July 20, 1881.

To all lwhom it may concern:

Be it known that I, JAMES A. TTLDEN, of Hyde Park, Norfolk county, State of Massachusetts, have invented an Improvement in FluidEnginesorMeters, of which the following description, in connection with the accompanying drawings, is a specification. i

My invention relates to aiiuid engine or meter, and is intended as an improvement on the Io meter formerly invented by me, upon which VLetters Patent No. 248,679 were granted October 25, 1881, to which reference may be had.

In my present invention, as in the former, the engine consists of a cylinder containing a main piston i Aitself formed as a cylinder, in

which a` secondary piston operates, the passages of the said cylinder and pistons being such that one piston acts as a valve to control the operation of the other.

My present invention'consists in a different arrangement of the said ports, having for its object to insure the more perfect operation of the engine,in which the main piston at the end of its Stroke brings passages into the proper 2 5 relation to admit tluid in one end thereof, and

permit it to pass from the other end to cause the secondary piston to make its stroke therethrough, at the end of which the said secondary piston brings its ports into Stich relation 3o 'as to admit the actuating-fluid to one end of the main cylinder and permit it to pass from the other end thereof. When the flow of fluid is very slow there is a liability, especially after the ports are somewhat worn,that the main 3 5 piston will begin to move before the secondary one has wholly'completed its movement and fully opened the ports, admitting the fluid to actuate the main piston, so that the said main pistonis retarded `in its movement. In my 4o present invention I obviate this difficulty by causing the main piston, during its movement,

to again admit the tluid to the secondary pis'- ton, causing its stroke to be completed with certainty.

Throughout the following description the termfmain77 will be applied to those passages through which the fluid passes to operate the main piston, and the term secondary7 to' those passages traversed by the fluid in oper- 5o ating thesecondarypiston. The main or outer (Model.)

Vcylinder is provided with depressions near its ends on the side provided with the inlet for theactuating-tluid, the said depressions being properly arranged to connect the main inletport, through which the fluidenters to actuate the main piston, with the secondary inlet-port, through which the fluid enters the main pistou` to actuate the secondary piston, so that just at the end of the stroke of the main pistou the tiuid is acting upon both it and the secondary piston, and, owing to the greater area ofthe mam piston, will insure its completin g its stroke. After the secondary piston has nearly or wholly completed its stroke and the main piston begins to make its returnstroke, the said depression in the cylinder will connect the secondary inlet-port With theend of the main cylinder that is receiving the actuating-fluid, and consequently the said actuating-duid will again act upon the second piston, causing it to complete its stroke if it has not alreadydoneso. While the secondaryT piston is thus receiving a Second impulse from the actuating-fluid theother end of the main piston, or that from .which the Huid-was exhausted when the secondary piston madeits last stroke, is connected by the other depressiion in the main cylinder with the end of the main cylinder from which the iiuid is being exhausted to lpermitthe movement ofthe piston, so that in the movement of the secondary piston causedby its second impulse the fluid before it has an exhaust-passage, together with the duid exhausting before the main piston.

Figure 1 is a vertical longitudinal section on line :o or, Fig. 2, of a fluid-engine meter constructed in accordance with my invention Fig. 2, a vertical section in line y y, Fig. 1, on pla-ne at right angles to that ot' Fig. 1, the parts being shown in both figures in the position in which the main piston has just com-l pleted its Stroke and the secondaryy piston is about to makea Stroke. Fig. 3 is a section on the same plane as that of Fig. 1, the pistons being shown in elevation in a position assumed 95 after the secondary has completed its stroke lfrom the position shown in the rsttwo figures and the main piston has begun its stroke, the fluid being admitted to give a second impulse upon the secondarypiston. Fig. 4 is a diagram wo the cylinder a, is provided with a passage, e,l

The main or outer cylinder, a, is provided" with an inlet-passage, b, and outlet-passage 0, located at its sides and at the middle ot' its length, and is also provided with depressions 2 3 near its ends, on the lsame side with the inlet-passage b.

The main piston d, tilted to reciprocate in through the middle of its side, entering from a depression, e', in the outer surface of the cylinder, sufficiently extended to remain in connection with the inlet-port b during the entire stroke ot the said piston d, and to connect the said inlet-port b withthe depressions 2 3 ot' the cylinder at the end ot' each stroke, respectlively, of the said main piston., as shown in Fig. l. The main piston d is also provided with secondary inlet-passagesff, which are connected at the end ot' the stroke of the main piston by the depressions 2 3 and the enlarged port of the opening e with the inlet-passage b, .as shown in Fig. l, so that the fluid is permitted at the end ofthe stroke ot' the main piston to enter the said main piston and operate upon the secondary piston. The main piston is also ,provided with a main exhaust-passage, la, upon the same side with the outlet-passage c of the cylinder, and of proper size to remain in connection therewith during the entire stroke of the said main piston, which is also provided with secondary exhaust-passages ij, which are .properly extended upon its outer surface to be brought into connection with the outlet c of the cylinder at the end of the stroke of the` ymain piston, as shown in Fig. l, where the ports are in proper position to receive tluidv .through the passage b, opening e, depression 2, and secondary inlet f to one end of the main piston, to operate upon thesecondary piston, and to permit the exhaust ot' the fluid from .theother end ot' the main piston through the secondary eXhaust-passagej and exhaust-passagec. y

The secondary piston k is made hollow and provided with a main inlet-passage, l, properly arranged to remain throughout its stroke inf connection with the main inlet-passage e ofthe main piston, so that the iiuid always has a free.

.with ports op (see Figs. 2 and 3) in the main piston leading tothe ends of the main cylinder, .and operating as inlet and exhaust ports alter- .nately. ,As shown in Fig. 2, the port a is still in con-y nection with the port p, in which position it' has permitted the iiuid to enter the main cylinder and cause the stroke of the main piston l to be made. The secondary piston is also provided with a channel, l#,in its exterior surface, passing spirally from a position on the same l.and canse it to complete its stroke.

side with the inlet-port m, and nearer the other end of the secondary piston, around the side-ot' the secondary piston adjacent to the outletpassage o ofthe cylinder to the saineside with the inlet-port n, and at the opposite end of the secondary piston. The said channel r is of such width that it always remains in connection with the main exhaust-port li, and it has one of its ends brought into connection with one ofthe ports op of the main piston at the end ot' the strolie, by which the other one ot' the said ports is connected with that one of the inlet-ports in n which is adjacent to the other end ot' the said channel i, so that while the fluid is passing from the interior of the second ary piston through the ports a and p, for instance, to one end ot' the main cylinder the fluid is passing from the other end otfthe main cylinder through the port o, channel i", and passages h and c, thus causing the main piston to make its stroke, which is shown asjust tinished in Figs. l and 2, and at theend ofwhich the secondary portsfand g' arebrought in position .to cause the secondary piston to vmake a stroke, at the end lof which the inlet-port m will be brought in connection with the port o and the channel r with the portp, to cause the main piston to make its return-stroke.

When the uid is moving very slowly, as

lmay be. the case in vaV water-meter, the main ICO ot' the cylinder that is receiving fluid through the main inlet-passages m o, to thus permit the iiuid to again act upon the secondary piston At the saine time the secondary inlet-passage g at the other end of the main piston will be connected by the ydepression 3 with the end of the cylinder from which the fiuid is passing through theport p, channel r, and passages hand 0, the said port g inthis instance acting as a secondary exhaust-port tor the time being until the stroke of the secondary piston is completed.

In order to equalize the wear of the surface of the pistons and cylinders,the-apparatus is vpreferably so placed that the said pistons reports with the said inlet-passa ge ot' the cylinder passage and `with internal depressions in the side thereof, combined with the main piston .provided with secondary inlet-ports and a depression in its surface in connection with the said inlet-passage throughout its stroke, and acting in co-operation with the said depressions of the cylinder to connect the secondary inlet- `atdenite points in the stroke of the main piston, substantially as described. 2. The cylinder provided with inlet and outlet passages and with the internal depressions all in its sides, combined with the main piston provided with the secondary inlet-por`ts, and the secondary pistou therein,the said ports and depressions being arranged, as described, to connect the interior of the main piston at each end with the corresponding end ot' the cylinder during a portion of the stroke of the main piston, substantially as and for the purpose set forth. i

3. The main cylinder provided with an outlet-passage, and the main piston therein provided with a main outlet-port in connection with the said passage throughout its stroke, and with ports leading to the main cylinder at either end of the said piston, combined with the secondary piston provided with an external channel always in connection with the said main outlet-port and with main inletports, ar- 3o ranged as described, whereby one of the said main inlet-ports is in communication with the port ot' the main piston leading to one end of the cylinder, while the corresponding port leading to the other end ot' the cylinder is in com- 35 

